a) Field of the Invention
The present invention relates to a method for predicting the total amount of gas to be produced from a coke oven battery.
b) Description of the Prior Art
A coke oven battery used for producing coke generally consists of a plural number of coke ovens. In order to produce coke with the coke oven battery, coal is charged as the raw material into the coke ovens sequentially at definite time intervals and coke is discharged sequentially after production. In such a coke oven battery, gas is produced from the individual coke ovens. The produced gas is collected from the coke oven into a duct for discharge outside the oven.
The gas produced in the coke oven battery contains gas oils such as benzene and toluene as well as other components, which are recovered for utilization by a process, for example, of desulfurization or gas oil recovery, whereas remaining coke oven gas (COG) which is not recovered is utilized as a fuel.
When COG production rate from a coke oven battery varies, it is possible to enhance recovering efficiency by controlling conditions in the process to recover the above-mentioned components in accordance with the variation of the production rate or when the COG is to be used as a fuel, it may be necessary to control feed rate in accordance with production rate so as to keep good balance between demand and supply.
For this reason, it is important to predict amount of gas to be produced from the coke oven battery.
As the conventional method, it is already known to predict total amount of gas to be produced from a coke oven battery by preliminarily determining a unit quantity of coal charged into each coke oven and empirically (or experimentally) determining parameters of variation with time lapse of production rate per unit quantity of coal at the stages from charging of coal to discharge of coke. Speaking concretely, on the basis of actual achievements, production rate q.sub.0 per unit quantity of charged coal at the charging time, production rate q.sub.1 at time t.sub.1 after charging, . . . and production rate q.sub.n at time t.sub.n after charging or at the discharging time are used as quantity of coal charged at time t.sub.n before the present the parameters on the basis of actual achievement, whereas time is represented by W.sub.-n, quantity of coal charged at time t.sub.n-1 before the present time is designated by W.sub.-(n-1), . . . and quantity of coal charged at the present time is denoted by W.sub.0 as shown in FIGS. 4 and 5. Then, a total amount of produced COG is determined by the following equation: EQU W=W.sub.0 q.sub.0 +W.sub.-1.sbsb..cndot. q.sub.1 + . . . +W.sub.-n.sbsb..cndot. q.sub.n
However, it is impossible to correctly predict a total amount of COG by this method since gas production rate per unit quantity of charged coal is varies depending on variations of various conditions such as operating condition of the coke oven battery and quality of charged coal. Accordingly, it is necessary to perform calculations for prediction with the parameters and production model corrected or modified in accordance with the variations of the coking conditions, thereby making it necessary to collect a large quantity of data and prepare the parameters and productions models based on data while consuming a long time and a large amount of labor.
The predicting methods disclosed by Japanese Unexamined Published Patent Applications No. 240789/60 and No. 121088/57 are known as the conventional examples but have the above-described defects that sufficiently satisfactory prediction is impossible.